Electric receptacle



July 19, 1960 E. T. PLATZ ETAL 2,946,037

ELECTRIC RECEPTACLE Filed Aug. 10, 1955 INVENTOR5. E /woo? 7. 22 5 7 8777771 United States Patent ELECTRIC RECEPTACLE Elwood T. Platz, Detroit,John B. Cataldo, Birmingham, and John A. Herrmann, Grosse Pointe Farms,Mich.,

- assignors, by mesne assignments, to I-T-E Circuit Breaker Company,Philadelphia, Pa., a corporation of Pennsylvania Filed Aug. 10, 1955,Ser. No. 527,621

9 Claims. (Cl. 339-154) efficient connection in an electricaldistributionsystem.

Another object of the invention is to provide a receptacle which cannotbe installed or removed when under electrical load.

Another object is to provide a receptacle which is easily and positivelyattached and removed from a distribution system.

Still another object is to provide a receptacle which is automaticallylocked in a distribution system when a plug cap is in place.

Still another object is to provide a receptacle in which the contactspositively and efliciently engage the conductors of a distributionsystem.

Still another object is to provide a receptacle which can not beaccidentally disengaged from an electrical distribution system.

Still another object is to provide a receptacle of simple constructionwhich is easily assembled of a minimum number of parts.

Still other objects and features will appear from the followingdescription and drawings, in which:

Fig. 1 is an elevational view of a portion of an electrical distributionsystem showing a receptacle which is an embodiment of the invention. p

Figure la is a right angle view of Figure l.

Fig. 2 is an elevational view of the back of the receptacle showing therelationship of the parts when the receptacle is installed in adistribution system.

Fig. 3 is an elevational view of the back of the receptacle showing therelationship of the parts prior to installation of the receptacle in adistribution system.

Fig. 4 is a cross-sectional view on line 4-4 of Fig. 2.

Fig. 5 is a cross-sectional View on line 55 of Fig. 3, and t ,Fig. 6 isan exploded view of the receptacle showing the component parts indetail.

Figure 6a is a side view of the locking member.

Referring to the drawings Fig. 1 shows a receptacle 11 which is anembodiment of the invention engaged with the duct 12 of a multi-outletelectrical distribution system. The particular duct shown is anembodiment of the invention shown and described in abandoned applicationNumber 252,272, which was filed October 20, 1951, with William H. Frank,John A. Herrmann, Elwood T. Platz, and Joseph A. Messing as inventorsand which is assigned to the assignee of this application. The duct .12is preferably formed of a plastic material and includes a wall PatentedJuly 19, was

12a having the upper and lower portions folded down- Wardly. andupwardly, respectively, to form lips 12b and 120 which encloseelectrical conductors (Figure 1a). Formed integrally with the wall 12intermediate lips 12b and 120, to one side of the center line of duct 12is a polarizing rib 12d. The duct forms no part of this invention, andfor a more detailed description of that invention, reference is made tothe above-mentioned application.

As shown in Fig. 6, the receptacle 11 includes a molded one-piecehousing 13 of plastic material, a pair of contacts 13a (Figs. 4, 5, 6)and a locking member 13c (Figs. 2, 3, 6, 6a), which will be described ingreater detail. The lower portion of the housing 13 comprises a base 14.The top wall 15 of housing 13 is recessed, as shown (Figs. 1, 4, 5), andcontains plug prong openings 16, which permit insertion of theconventional plug cap prongs. The interior of housing 13 is formed toprovide a cylindrically-shaped cavity 13c (Fig. 6), which receives andjournals portions of lock member 130. Opening into the wall of cavity13e are contact slots 16a which are partly filled by abutments 17opposite, and of thesame width as, the opening. in the wall of cavity13e., These abutments 17 extend the length of slots 16a to theundersurface of the top wall 15 to a point spaced from the outer edge ofprong openings 16. A smaller cylindricallyshaped recess 18 (Fig. 6) isformed in the undersurface of the top wall 15. At the right side (Fig.6) a portion 19 of the edge of cavity 13a is beveled to form clearancefor a reinforcing web on the lock member 130. A portion 20 of the leftedge (Fig. 6) of cavity 13a is cut away rectangularly to provide a lockmember stop. An index marker 29 of arrow shape is embossed in the upperright corner of the lower surface of base 1 4 of housing '13 (Figs. 2,3,6).

Contacts 13a are made of a resilient electrically conductive metal, suchas Phosphor bronze. As shown in Figs. 4, 5, and 6, each contact isformed with a rectangular center-portion 21 having serrated lugs 22stamped and bent outwardly from each side to secure each contact 13awithin slot 16a. Extending from the lower side of rectangular centerportion 21 is a load contactor 23 which is formed by bending aprojecting tongue back upon itself. Extending from the opposite side ofcenter portion 2'1 and bent at an anglesof 90 is a line contactor 24 ofU shape with the lower leg of parallelogram shape. A locking indentation28 is formed in the bight of the U. The upper edge is serrated toprovide teeth 25 which insure good electrical contact when thereceptacle is engaged with the duct 12.

Disposed in cavity 13e of housing 13 is a locking member 13c: (Figs. *4,5, 6, 6a). This member is substantially T-shaped with a cylindricalupper portion 13 and a projecting rectangular lower portion 13g (Fig..6).

Upper portion 13) is formed with two collars 13k, 13k, one at the lowerend and one adjacent to the upper end of portion 13g, each containingdiametrically opposed notches 13m which permit plug cap prongs to beinserted into the interior of housing 13 when the receptacle 11 isinstalled upon the duct 12. The upper surface of the lower collar 13k isbeveled, as shown in Figs. 5 and 6.

A locking lug 13a projects from the periphery of the upper collar :13k'and seats itself in top '20 of housing 13 upon assembly of thereceptacle. A cylindrical projection 31 extends from the bottom surfacewhich is received by journal 18 in top wall 15 of housing 13. Atriangular-shaped web 39 shown in Figure 6a is formed on the oppositeside of upper collar 13k from guidelug 13n and seats itself on thebeveled edge 19 of cavity 13c of housing 13. The locking member 13c isretained in cavity He by the engagement of the bight portion of linecontactors 24 with a tapered shoulder of the lower collar 13k of lockingmember 13c (Figs. 2, 3, 6).

Lower portion 13g of lock member 13c is substantially rectangular inshape with portions being cut away, as shown (Figs. 2, 3, 6) to formrelief slots 32, which provide clearance for line contactors 24 whenhousing 13 is rotated to the disengaged position for removal of thereceptacle 11 from the duct 12. Extending longitudinally of the uppersurface of upper portion 13g of lock member 130 is a polarizing slot 33located off center, which receives polarizing rib 12d of duct 12 toposition and secure the receptacle to duct 12. Projections 35 are formedin the defining surface of relief slots 32 to cooperate withindentations 28 of line contactors 24 to index the locking member 130 tothe disengaged position as shown in Fig. 3. A locking member index 36 ofarrow shape is embossed in the'lower right corner of lock member 13c tocorrelate the respective positions of housing 13 and locking member 13cprior to installation of receptacle 13 on the duct '12.

It will be observed, therefore, that the locking member 130 is rotatablerelative to housing 13 through an angle of approximately 45 as limitedby the engagement of locking lug 1311 with the end walls of 20.

The receptacle functions as follows: In the disengaged position of Fig.3 the upper collar 13k is beneath prong openings 16 of housing 13, thuspreventing the insertion of plug cap prongs into openings 16. It isnecessary, therefore, to first place the receptacle 13 on.

the duct 12 before the plug connection can 'be made. To attach thereceptacle to the duct 12, the respective indexes, 36 on locking member130, and 29 on housing 13, are aligned, as shown in Fig. 3. In thisposition load contactors 25 are disposed in relief slots 32. The lockingmember 13c is then placed against the duct 12 between upper and lowerlips 12b, 12c with polarizing rib 12d disposed in polarizing slot 33.Because of the Oh center location of rib 12d and slot 33, the receptaclecan be placed on the duct 12 only in a position which conforms to thepolarization of the system. In this position the housing 13 Will bedisposed at an angle of approximately 45 with the centerline of duct 12.To complete the attachment of the receptacle 11 to the duct 12, thehousing 13 is rotated clockwise, forcing line contactors24 beneath lips12b, 120 into engagement with the duct conductors. Serrations 25 of linecontactor 2'4 will penetrate the surface of the conductors, assuringelectrical conductivity between the duct conductors and the contacts13a. The plug cap may then be installed by inserting the plug cap prongsin openings 16 of housing 13. Upon being pushed in, the plug cap prongswill engage the inner surface of load contactors 23. The inward bias ofload contactors 23 assure electrical conductivity between the .plug capprongs and the load contactors 23. The electrical circuit is thusestablished from the duct conductors to line contactors 24 to loadcontactors 23 to the plug cap prongs to the particular equipment desiredto be electrically serviced. In this position (Fig. 1) with the plug capprongs inserted into the receptacle 11 the prongs are disposed in slots1311 of locking member 130. The rotation of housing 13 relative tolocking member 130 is thus prohibited. Removable of recptacle 11 fromthe duct 12 is therefore impossible while the plug cap is engaged withreceptacle 11.

To remove the receptacle 11 from duct 12, the plug cap is withdrawnremoving the plug cap prongs from engagement with slots 13m of lockingmember 130 and load contactors 23. Housing 13 is then rotatedcounterclockwise, removing line contactors 25 from beneath lips 12!),120 of duct 12 into alignment with the edges of locking member 130 aspermitted by relief slots 32. The receptacle may then be removed fromthe duct 12.

From the above description it can be seen that the locking member 13cengages the duct polarizing rib 12d and the inner edges of lips 12b, 120to provide a fulcrum for relative movement of housing 13 when thereceptacle 1 1 is being installed, or removed from, the duct 12.Furthermore, the receptacle 11 cannot be removed from the duct 12 otherthan in the manner above described. The construction of the contacts 13aprovide efficient electrical current transmission from the ductconductors through receptacle 11 to the equipment to be energized.

For an understanding of the scope of the invention, reference should behad to the following claims.

We claim:

1. An electrical receptacle including a housing having plug openingstherein, electrical contacts disposed in said housing, each contacthaving a load contactor adjacent one of said openings, a locking membermovable relative to said housing, said locking member having polar izingmeans for polarizing said receptacle in an electrical distributionsystem, said locking member having obstrucing means positionable in saidopenings for selectively prohibiting the attachment of a plug cap tosaid receptacle, said contacts having portions engaging said lockingmember to thereby secure said locking member in said housing. 7

2. An electrical receptacle including a housing having plug openingstherein, electrical contacts disposed in said housing, each contacthaving a load contactor and a line contactor, each of said loadcontactors being adjacent'one of said openings, a locking member movablerelative to said housing, said locking member having obstructing meanspositionable in said openings for selectively prohibiting the attachmentof a plug cap to said receptacle, said contacts having portions engagingsaid locking member to thereby secure said locking member in saidhousing, said locking member having its outer surfaces shaped tocooperate with said housing and form passageways for the reception ofsaid line contactors to thereby permit said receptacle to be installedin an electrical distribution system.

3. An electrical receptacle including a housing having plug openingstherein, electrical contacts disposed in said housing, each contacthaving a load contactor and a line contactor, each of said loadcontactors being adjacent one of said openings, a locking member movablerelative to said housing, said locking member having polarizing meansfor polarizing said receptacle in an electrical distribution system,said locking member having obstructing means positionable in saidopenings for se ectively prohibit'ing the attachment of a plug cap tosaid receptacle, said contacts having portions engaging said lockingmem-' her to thereby secure said locking member in said housing, saidlocking member having its outer surfaces shaped to cooperate with saidhousing and form passageways. for the reception of said line contactorsto thereby permit said receptacle to be installed in an electricaldistribution system.

4. An electrical receptacle including a housing having plug openingstherein, electrical contacts disposed in said housing, each contacthaving a load contactor and a line contactor, each of said leadcontactors being adjacent one of said openings, a locking member movablerelative to said housing, said locking member having obstructing meanspositionable in said openings for selectively prohibiting the attachmentof a plug cap to said receptacle, said contacts having portions engagingsaid locking member to thereby secure said locking member in saidhousing, said housing having bearing means for supporting and guidingsaid locking member, said locking member having its outer surfacesshaped to cooperate with said housing and form passageways for thereception of said line contactors to thereby permit said receptacle tobe installed in an electricaldistribution system.

5. An electrical receptacle including a housing having plug openingstherein, electrical contacts disposed in said housing, eachcontacthaving a load contactor and a line contactor, each of said loadcontactors being adjacent one of said openings,.a locking member movablerelative to said housing, said lock-ing member having polarizing meansfor polarizing said receptacle in an electrical distribution system,said locking member having obstructing means positionable in saidopenings for selectively prohibiting the attachment of a plug cap tosaid receptacle, said contacts having portions engaging said lockingmember to thereby secure said locking member in said housing, saidhousing having bearing means for supporting and guiding said lockingmember, said locking member having its outer surfaces shaped tocooperate with said housing and form passageways for the reception ofsaid line contactors to thereby permit said receptacle to be installedin an electrical distribution system.

6. An electrical receptacle being comprised of a housing; a lockingmember, a pair of contacts; each of said contacts including a linecontactor and a load contactor; said contacts being disposed within saidhousing and being secured thereto to move in unison therewith; saidhousing including prong openings adjacent to each of said loadcontactors; said locking member being mounted within said housing andjournalled thereby for limited rotation with respect thereto; saidlocking member including a collar having notches cut therein; saidnotches being in alignment with said prong openings when said lockingmember is rotated to a first position to thereby permit the mounting ofa plug cap to said receptacle; said collar being interposed between saidload contactors and said prong openings when said locking member isrotated to a second position to thereby prevent the mounting of a plugcap to said receptacle.

7. An electrical receptacle being comprised of a housing; a lockingmember, a pair of contacts; each of said contacts including a linecontactor and a load contactor; said contacts being disposed within saidhousing and being secured thereto to move in unison therewith; saidhousing including prong openings adjacent to each of said loadcontactors; said locking member being mounted within said housing andjournalled thereby for limited rotation with respect thereto; saidlocking member including a collar having notches cut therein; saidnotches being in alignment with said prong openings when said lockingmember is rotated to a first position to thereby permit the mounting ofa plug cap to said receptacle; said collar being interposed between saidload contactors and said prong openings when said locking member isrotated to a second position to thereby prevent the mounting of a plugcap to said receptacle; said contacts including bight portionsoperatively positioned to retain said looking member within saidhousing.

8. An electrical receptacle being comprised of a housing; a lockingmember, a pair of contacts; each of said contacts including a linecontactor and a load contactor; said contacts being disposed saidhousing and being secured thereto to move in unison therewith; saidhousing including prong openings adjacent to each or said loadcontactors; said locking member being mounted within said housing andjournalled thereby for limited rotation with respect thereto; saidlocking member including a collar having notches cut therein; saidnotches being in alignment with said prong openings when said lockingmember is rotated to a first position to thereby permit the mounting ofa plug cap to said receptacle; said collar being interposed between saidload contactors and said prong openings when said locking member isrotated to a second position to thereby prevent the mounting of a plugcap to said receptacle; said locking member and said contacts includingcooperating latching means to latch said locking member in said secondposition.

9. An electrical receptacle being comprised of a housing; a lockingmember, a pair of contacts; each of said contacts including a linecontactor and a load contactor; said contacts being disposed within saidhousing and being secured thereto to move in unison therewith; saidhousing including prong openings adjacent to each of said loadcontactors; said locking member being mounted within said housing andjournalled thereby for limited rotation with respect thereto; saidlocking member including a collar having notches cut thereimcsaidnotches being in alignment with said prong openings when said lockingmember is rotated to a first position to thereby permit the mounting ofa plug cap to said receptacle; said collar being interposed between saidload contactors and said prong openings when said locking member isrotated to a second position to thereby prevent the mounting of a plugcap to said receptacle; said line contactors being operativelypositioned, when said locking member is in said second position, topermit said receptacle to be installed in a continuous outlet electricaldistribution system; said line contactors being operatively positioned,when said receptacle is installed in a continuous outlet electricaldistribution system and said locking member is in said first position,to contact the conductors of said system and cooperate with said systemto prevent the removal of said receptacle from said system; said lockingmember including a port-ion generally rectangular in shape having anotch therein positioned parallel to and spaced from the major axis ofsaid rectangle, said notch adapted to cooperate with a polarizing rib ofa continuous outlet electrical distribution system.

References Cited in the file of this patent UNITED STATES PATENTS723,866 Hart Mar. 31, 1903 2,399,408 Walk Apr. 30, 1946 2,659,874 VeitchNov. 17, 1953 2,741,749 Smith Apr. 10, 1956

